At present, most studies in this direction consider only the characteristics of the mean flow rate in the natural ventilation, which would lead to errors, because the wind is thus considered as a steady flow. In order to better evaluate the ventilation effects of naturally ventilated buildings, the fluctuating characteristics of the natural wind should be considered, and the impacts of the fluctuating characteristics on the natural ventilation rates are discussed in this paper. The prediction methods for the ventilation rates are divided into two types: the correction method based on the steady-state flow assumption and the fluctuation method based on the unsteady-state flow assumption. Meanwhile, the effects of the turbulence intensity and the pulsation frequency of the natural wind on the human thermal comfort are analyzed. It is pointed out that a natural ventilation model should be developed based on the fluctuating wind for the engineering design in China.